Improvement in steam-boilers



UNITED STATES PATENT OFFICE.

JOHN BowMAN AfrwATE, oE GENEVA, rLLrNors.

IMPROVEMENT INk STEAMf-BOILERS. Y

Speciiication forming part of vLetters Patent No'. 116,007, dated June 20, 1871.

'ta-ken vertically and transversely through the auxiliary steam-generator.

Similar letters of reference indicate corresponding parts in the two iigures. This 'invention relates to due-boilers, and has for its object the arrangement within the iire-chamber of such a lboiler ot' an auxiliary liuc-generator, interposfed between which la-tter and the front end of the primary boiler is a combustion-chamber, which is supplied with air through apertures made through one ofthe water-legs` surrounding the lire-chamber, as will be hereinafter explained.

To enable others skilled in the art to unden stand my invention, I will explain its construction and operation.

In the accompanying drawing I have represented my invention applied in the lire-cham ber of a locomotive flue-boiler; but it willbe obvious from the following description that it can be applied to other varieties of flue-boilers. 'A represents the lire-chamber of a boiler, which i's surrounded with a water-jacket communicating with thebody of the boiler in the wellknown manner. `B represents my improved auxiliary steam-generator, which is arranged in the lire-chamber A, and separated from the posterior head of the primary boiler by means of a combustion-chamber, C, into which air is introduced through one or more hollow bolts, g, as indicated by the arrow in dotted lines. The separation of the auxiliary generator B from the head ot' the primary boiler and its attachment thereto are effected by means of extensions e of the plates which surround this generator, as shown in Fig. l. The generator B is composed of front and rear heads, a surrounding shell, and short flue-tubes a a, which latter are secured by their extrern- Vities to the two heads of the generator, and

may or may not be coincident with the tubes b through the boiler proper. "E represents a tubular communication between the primary boiler and the auxiliary boiler or generator;

and D l) represent communications'between the generator and the steam-space above the Sfis the steamwater in the primary boiler. dome; J, the steam-pipe leading into a superheater, G, which is arranged inthe smoke-box j l. -The branch pipes s, which lead out ofthe superheater, communicate with the engine.

lt will be seen from the above description th at the iiame and products of combustion a-re all conducted from the tire-chamber A through the auxiliary generator B into a combustionchamber, C, before they enter the tubes b of `the boiler proper; that Ythese highly-heated products are supplied with air in ,the combus tion-chamber C, and thus thoroughly burned; that the upper surfaces of the tlues b are not exposed to the impin gement of ci n ders against them, and for this reason they will `lot be readily destroyed; th at the generator B, which is in communication with the water-space of .the primary boiler below and with the steam-l space of the boiler above, is subjected to intense heat at both ends, and consequently there the combustion-chamber C, arranged in front of a flue-boiler in the fire-chamber thereof, sub- I stantially as described.

JOHN BOWMANVATWATER. Witnesses:

P. HoYT, J. EVERTS.V 

